Beat the Heat this Summer with these Helpful Hints

July 23, 2013

No, it's not your imagination—it definitely is getting hotter. The eight warmest years on record occurred over the past decade. But staying cool this summer doesn't necessarily mean you have to pay a fortune to keep the air-conditioning running day and night. Here are 10 tips—most costing less than $25—that will keep you comfortable and cut the typical $1,000 cooling bill by as much as half. What's needed to get the temperature to drop? Only a little time and a few changes in your routine.

The Right Setting
Typical air-conditioning settings for a programmable thermostat at different times of day:

6 a.m. to 9 a.m. = 75 degrees

9 a.m. to 5:30 p.m. = 80 degrees

5:30 p.m. to 11 p.m. = 75 degrees

11 p.m. to 6 a.m. = 80 degrees

Set the Dial Higher
If you have central air, set your thermostat above 78 degrees (all temperatures cited here are in degrees Fahrenheit). You'll save 5 to 8 percent on cooling costs with each degree above that mark. For a typical household, setting the thermostat at 80 degrees saves 10 to 15 percent; raising it to 85 degrees will save 35 to 55 percent. When you leave home for more than one hour, set the thermostat to 85 or 90 degrees. Reset it upon your return, and the room will cool down in only 15 minutes. The system will use less energy during the cool-down period than if you had left it running at a lower setting while you were out.
Cost: $0
Benefit: 15 to 20 percent or more off your cooling bill

Use a Fan
A fan, which costs two to five cents per hour to operate, will make a room feel 4 to 6 degrees cooler. Also, a fan works well in tandem with an air conditioner because the dehumidifying action of the air conditioner provides drier air that the fan can then move around. In frequently used rooms, install a ceiling fan (set it to spin counterclockwise in summer). You'll save the most money by running the fan only when you're in the room. A motion-detector switch (around $20), which turns the fan on when you enter a room and off when the room is empty, is a good addition. However, if you have pets that move in and out of the room, make sure the switch can be turned off manually. Otherwise, your pets can cause the fan to run while you're away.
If nighttime temperatures drop into the 70s where you live, you might want to purchase a whole-house fan, which runs $300 to $600 installed. This type of unit goes in an upstairs ceiling, ideally in a central hall. When run at night with the windows open, the fan will pull cool air into the house as it vents hot air out through the attic. Most models are designed to slip in between joists for easy installation. Whole-house fans, which draw only as much power as a couple of light bulbs, are usually outfitted with a variable-speed switch and/or timer. If you install one, be sure to get an insulated box to cover the portal in winter.
Cost: Ceiling fans range from $30 to $200. Floor fans cost around $20, and whole-house fans run from $300 to $600.
Benefit: Ceiling fans can decrease your cooling bill by up to 15 percent, while a whole-house fan can slash it by 50 percent.

Use Sunblockers
As much as 20 percent of summer heat enters your home as sunlight shining through windows. To cut "solar gain," add curtains or blinds to rooms that get direct sun and draw them in daylight hours. With the shades drawn, a well-insulated house will gain only 1 degree per hour when outdoor temperatures are above 85 degrees. Pay special attention to west-facing rooms late in the day. Shades and blinds to consider include roller shades (the least expensive option), venetian-type micro-blinds, reflective curtains and insulated curtains (the most expensive, at $100 per window). Two exterior options are to install awnings or plant shade trees.
Cost: $8 to $100 per window
Benefit: Up to 20 percent off your cooling bill

Get Cooler Lights
Incandescent bulbs don't contribute as much heat as un-shaded windows, but they do add heat to a house and can raise the perceived temperature, sending you to the thermostat to seek relief. To reduce this hot-light effect and save lighting costs year-round, replace incandescent bulbs with compact fluorescents. They use about 75 percent less energy and emit 90 percent less heat.
Cost: $12 to $25 per bulb
Benefit: Up to 5 percent off your cooling bill plus electricity savings

Information contained in this article is courtesy of U.S. Green Building Council's Green Home Guide.